<template>
  <div class="article-container markdown-body">
    <!-- 导航栏 -->
    <van-nav-bar class="page-nav-bar" left-arrow title="黑马头条"></van-nav-bar>
    <!-- /导航栏 -->

    <div class="main-wrap">
      <!-- 加载中 -->
      <div class="loading-wrap" v-if="loading">
        <van-loading color="#3296fa" vertical>加载中</van-loading>
      </div>
      <!-- /加载中 -->

      <!-- 加载完成-文章详情 -->
      <div class="article-detail" v-else-if="article.title">
        <!-- 文章标题 -->
        <h1 class="article-title">{{ article.title }}</h1>
        <!-- /文章标题 -->

        <!-- 用户信息 -->
        <van-cell class="user-info" center :border="false">
          <van-image class="avatar" slot="icon" round fit="cover" :src="article.aut_photo" />
          <div slot="title" class="user-name">{{ article.aut_name }}</div>
          <div slot="label" class="publish-date">{{ article.pubdate | relativeTime }}</div>
          <!-- 关注组件 -->
          <follow-user v-model="article.is_followed" :aut_id="article.aut_id"></follow-user>

          <!-- <van-button v-if="!article.is_followed" class="follow-btn" type="info" color="#3296fa" round size="small" icon="plus" @click="followUser" :loading="isLoading">关注</van-button>

          <van-button v-else class="follow-btn" round size="small" @click="followUser" :loading="isLoading">已关注</van-button> -->
        </van-cell>
        <!-- /用户信息 -->

        <!-- 文章内容 -->
        <div class="article-content" v-html="article.content"></div>
        <van-divider>正文结束</van-divider>

        <!-- 文章评论 -->
        <article-comment :list="list" :source="article.art_id" @onLoad-success="commentsCount = $event.total_count" @replay="onReplay"></article-comment>

        <!-- 底部区域 -->
        <div class="article-bottom">
          <van-button class="comment-btn" type="default" round size="small" @click="comment_show = true">写评论</van-button>
          <van-icon name="comment-o" :badge="commentsCount" color="#777" />
          <!-- 收藏组件 -->
          <article-collect v-model="article.is_collected" :article_id="article.art_id"></article-collect>
          <!-- <van-icon color="#777" name="star-o" /> -->
          <!-- 点赞组件 -->
          <like-article v-model="article.attitude" :article_id="article.art_id"></like-article>
          <!-- <van-icon color="#777" name="good-job-o" /> -->
          <van-icon name="share" color="#777777"></van-icon>
        </div>
        <!-- /底部区域 -->
        <van-popup v-model="comment_show" position="bottom">
          <comment-post :target="article.art_id" @comment-success="onCommentSuccess"></comment-post>
        </van-popup>
      </div>
      <!-- /加载完成-文章详情 -->

      <!-- 加载失败：404 -->
      <div class="error-wrap" v-else-if="statusCode === 404">
        <van-icon name="failure" />
        <p class="text">该资源不存在或已删除！</p>
      </div>
      <!-- /加载失败：404 -->

      <!-- 加载失败：其它未知错误（例如网络原因或服务端异常） -->
      <div class="error-wrap" v-else>
        <van-icon name="failure" />
        <p class="text">内容加载失败！</p>
        <van-button class="retry-btn">点击重试</van-button>
      </div>
      <!-- /加载失败：其它未知错误（例如网络原因或服务端异常） -->
    </div>
    <van-popup v-model="isReplyShow" position="bottom" :style="{ height: '100%' }">
      <comment-reply v-if="isReplyShow" :comment="currentComment" @close="isReplyShow = false"></comment-reply>
    </van-popup>
  </div>
</template>

<script>
import { ImagePreview } from 'vant' // 图片预览
import { getArticleById } from '@/api/article'
import { addFollow, deleteFollow } from '@/api/user'
import FollowUser from '@/components/follow-user'
import ArticleCollect from '@/components/article-collect'
import LikeArticle from '@/components/like-article'
import ArticleComment from './components/article-comment'
import CommentPost from './components/comment-post'
import CommentReply from './components/comment-reply'
export default {
  name: 'ArticleIndex',
  components: {
    FollowUser,
    ArticleCollect,
    LikeArticle,
    ArticleComment,
    CommentPost,
    CommentReply
  },
  provide: function () {
    return {
      art_id: this.id
    }
  },
  props: {
    id: {
      type: [Number, String, Object],
      required: true
    }
  },
  data () {
    return {
      list: [],
      article: {},
      loading: true, // 刚开始ajax请求没有回来之前，显示的是loading加载中效果
      statusCode: 0, // 错误显示有两种，一种是404，一种是其他
      isLoading: false,
      commentsCount: 0, // 从评论组件获取的评论数量
      comment_show: false, // 评论文章弹层
      isReplyShow: false, // 评论回复弹层
      currentComment: {}
    }
  },
  computed: {},
  watch: {},
  created () {
    this.loadArticle()
  },
  mounted () { },
  methods: {
    async loadArticle () {
      try {
        const { data: res } = await getArticleById(this.id)
        // console.log(res)
        this.article = res.data
        console.log(this.article)
        this.preview()
      } catch (err) {
        if (err.response.status === 404) {
          this.statusCode = 404
        } else {
          this.$toast.fail('获取新闻文章详情失败')
        }
      }
      this.loading = false
    },
    // 图片预览
    preview () {
      setTimeout(() => {
        var imgs = document.querySelector('.article-content').querySelectorAll('img')
        var arr = []
        imgs.forEach((item, index) => {
          arr.push(item.src)
          item.onclick = function () {
            ImagePreview({
              images: arr,
              startPosition: index
            })
          }
        })
      }, 0)
    },
    async followUser () {
      this.isLoading = true // 开启loading效果
      try {
        if (this.article.is_followed) {
          // 取消关注
          await deleteFollow(this.article.aut_id)
        } else {
          // 添加关注
          await addFollow(this.article.aut_id)
        }
        this.article.is_followed = !this.article.is_followed
      } catch (err) {
        if (err.response && err.response.status === 400) {
          return this.$toast.fail('不能关注自己')
        }
        this.$toast.fail('关注操作失败')
      }
      this.isLoading = false // 关闭loading效果
    },
    onCommentSuccess (data) {
      console.log(data)
      this.comment_show = false
      this.list.unshift(data.new_obj)
    },
    onReplay (comment) {
      console.log(comment)
      this.currentComment = comment
      this.isReplyShow = true
    }
  }
}
</script>

<style scoped lang="less">
@import '~@/styles/github-markdown.css';
.article-container {
  .main-wrap {
    position: fixed;
    left: 0;
    right: 0;
    top: 92px;
    bottom: 88px;
    overflow-y: scroll;
    background-color: #fff;
  }
  .article-detail {
    .article-title {
      font-size: 40px;
      padding: 50px 32px;
      margin: 0;
      color: #3a3a3a;
    }

    .user-info {
      padding: 0 32px;
      .avatar {
        width: 70px;
        height: 70px;
        margin-right: 17px;
      }
      .van-cell__label {
        margin-top: 0;
      }
      .user-name {
        font-size: 24px;
        color: #3a3a3a;
      }
      .publish-date {
        font-size: 23px;
        color: #b7b7b7;
      }
      .follow-btn {
        width: 170px;
        height: 58px;
      }
    }

    .article-content {
      padding: 55px 32px;
      /deep/ p {
        text-align: justify;
      }
    }
  }

  .loading-wrap {
    padding: 200px 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #fff;
  }

  .error-wrap {
    padding: 200px 32px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background-color: #fff;
    .van-icon {
      font-size: 122px;
      color: #b4b4b4;
    }
    .text {
      font-size: 30px;
      color: #666666;
      margin: 33px 0 46px;
    }
    .retry-btn {
      width: 280px;
      height: 70px;
      line-height: 70px;
      border: 1px solid #c3c3c3;
      font-size: 30px;
      color: #666666;
    }
  }

  .article-bottom {
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    display: flex;
    justify-content: space-around;
    align-items: center;
    box-sizing: border-box;
    height: 88px;
    border-top: 1px solid #d8d8d8;
    background-color: #fff;
    .comment-btn {
      width: 282px;
      height: 46px;
      border: 2px solid #eeeeee;
      font-size: 30px;
      line-height: 46px;
      color: #a7a7a7;
    }
    .van-icon {
      font-size: 40px;
      .van-info {
        font-size: 16px;
        background-color: #e22829;
      }
    }
  }
}
</style>
